Questions tagged [superblock]

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44
votes
4answers
177k views

Recovering ext4 superblocks

Recently, my external hard drive enclosure failed (the hard drive itself powers up in another enclosure). However, as a result, it appears its EXT4 file system is corrupt. The drive has a single ...
5
votes
1answer
4k views

How can I dump the contents of a filesystem's superblock?

I understand that I can list the location of a filesystem's superblocks using the following commands. Example First get the device handle for the current directory. $ df -h . Filesystem ...
5
votes
1answer
2k views

Difference between backup superblocks

Recently I accidentally formatted an EXT4 partition to FAT. I got into a panic. After a long journey through a dark wood in which my hope was fading I could recover my partition and it seems ok. After ...
5
votes
1answer
13k views

e2fsck: unable to set superblock flags on LogicalVolume

When I boot my machine either in normal mode or runlevel 1 it throws following error and I'm unable to boot the machine: checking filesystems /dev/MyGroup/LogVol00: UNEXPECTED INCONSISTENCY; RUN ...
5
votes
0answers
2k views

Btrfs super-recover says all superblocks are good but mount disagrees

I have an external drive formatted with BTRFS that seems refuses to mount: $ sudo mount -vs -t btrfs -o ro,recovery,errors=continue /dev/sdb2 /media/user/dir mount: /dev/sdb2: can't read superblock ...
4
votes
3answers
7k views

lost superblock in md raid

Issue on Red Hat Linux 5. Due to some miscommunication two LUNs in our environment were enlarged from 1.2 TB to 1.7 TB. Now, after a reboot, mdadm does not find the superblocks to build the array ...
4
votes
1answer
3k views

mdadm - Accidentally ran “mdadm --create” on an existing raid-1. The superblock is now corrupt and I am unable to recover data. Did I bork my data?

I have /dev/sdb1 and /dev/sdc2 that were previously setup into a RAID-1 with mdadm, but then I reinstalled and lost the old configuration. Out of idiocy, I ran sudo mdadm --create /dev/md0 --level=1 ...
3
votes
3answers
3k views

Data recovery from an accidental format on ext4 partition

When I was installing Mint Debian edition unlike the classic edition, the installation automatically formated my home partition when I did not specify to format. So the formatting previously was ext4 ...
3
votes
3answers
3k views

How can I identify the filesystem/partition type

My hard drive got corrupted at some point after mounting an mtpfs system. I would ask how to fix that, but I'm not confident about the partition and file system types. My OS is new Fedora Core 23, ...
3
votes
2answers
3k views

Creating disk device in a file

I'm trying to create disk device in a file with: dd if=/dev/zero of=file.img bs=516096 count=1000 sudo losetup /dev/loop0 file.img (echo n; echo p; echo 1; echo ""; echo ""; echo w;) | sudo fdisk -u -...
3
votes
1answer
2k views

Ext2 block structure: size of reserved GDT Blocks

In every publication I found about ext2, the structure of a block group is defined as following: Super Block: 1 block Group Descriptor: N blocks Data Bitmap: 1 block Inode Bitmap: 1 block Inode Table:...
3
votes
1answer
3k views

All my superblocks are corrupt!

I am having a problem with my ubuntu ext3 filesystem. I can't boot from it or mount the volume when running live CD. When I try e2fsck I get: "Bad magic number in super-block while trying to open /...
3
votes
1answer
729 views

Internal disk failed with bad superblock, how to fix? [closed]

NOTE: The operating system I'm using is on a separate disk (/dev/sdb). I tried to mount my old root partition (/dev/sda12) as usual with the following command: sudo mount /dev/sda12 /mnt However, ...
2
votes
2answers
703 views

mdadm metadata: should i take precautions to prevent superblock overwrite?

Situation: I'm creating a new RAID1 array using mdadm. I won't be using additional layers, such as LVM or dm-crypt. I've noticed that metadata version 1.2 is now the default. I understand it's the ...
2
votes
1answer
3k views

Unable to mount /home/ partition after reinstalling grub after reinstalling windows 7

I've reinstall windows 7 on it's asignated partition and, as usually, it override the MBR with it's own stuff and, thus, it was not possible to boot to my ubuntu 12.04 partition. I followed the step ...
2
votes
1answer
3k views

How to fix BTRFS superblock error after resize/shrink (BTRFS: couldn't get super buffer head for bytenr 274877906944)

BTRFS RAID1 array with 2 500 GB hdds, no errors. This is the root filesystem, so there are 3 partitions on each drive: 1 = /boot (ext4), 2 = / (btrfs), 3 (swap) /boot is ext4 because upgrading the ...
2
votes
1answer
685 views

mdadm + lvm2: destroyed all superblocks accidentally

I accidentally overwrote all my RAID1 superblocks with garbage. I think this happened because I ALT-CTRL-DEL booted when the Ubuntu had put me in some kind of hard disk recovery mode. My display wasn'...
2
votes
1answer
2k views

Physical volumes, logical volumes, superblocks gone… how to boot?

A story fairly similar to this one happened to me yesterday. Update: My only hard drive /dev/sda was originally partitioned this way: Device Boot Start End Blocks Id System /dev/...
2
votes
0answers
38 views

Why do my software RAID1 superblocks keep getting corrupted and how can I prevent this?

How might I be repeatedly corrupting my superblocks on RAID1 I have had two occasions in the past six months of RAID1 root arrays becoming unusable because of problems with the superblock. ...
2
votes
1answer
96 views

How to recover when ext4 superblock's inode count is reset to 0

We tried to resize a 15TB ext4 partition to 16TB and accidentally managed to hit an old (and fixed in newer releases) off-by-one bug of ext4_resize_fs() which causes inode count to reset to 0 thanks ...
2
votes
0answers
1k views

EXT4 app2sd link2sd partition repair with bad superblock . Partition cannot be mounted on Android but will mount RW w/ su on Linux Live

I have a 128gb micro sd formatted as ext4 10gb for app2sd 2nd ext4 partition ( p2 ) on my Android 6 phone . All my apps ( 80%) stay on that ext4 partition . Now app2sd cant load this partition - "...
2
votes
0answers
525 views

fsck fails frequently(after each 3-4 boots)

I have triple boot System(Ubuntu,Kali,Win7) and I mostly use Kali linux(4.6.0-kali1-amd64). After each 3 or 4 successful boots i get this error -> fsck.ext4: Superblock checksum does not match ...
2
votes
1answer
661 views

Short read while trying to open /dev/sda2

I just resized a .vdi from my host from 15.5G to 120G. I tried to resize the partition from the guest (ubuntu server) using resize2fs root@ubuntu:~# sudo resize2fs /dev/sda2 115G resize2fs 1.42.13 (...
2
votes
1answer
598 views

Relation between “Block Size”and “Upper Limits” in ext2

A similar looking question asks for the reason why the upper file limit could be 2 TB in ext2. I am trying to understand but the Documentation on ext2 but find this hard. Please correct me if I'm ...
2
votes
0answers
2k views

Superblock corruption on every boot

I have a Linux Mint 12 install on my laptop. Yesterday I powered it off like I always do and this morning when I started it I was greeted by an error screen. (Translated from Swedish) Fatal errors ...
1
vote
1answer
278 views

Superblock replicas in ext4

I am trying to find the association between block groups and superblocks in an ext4 filesystem I was unable to find much of documentation online, except this link that hints that Because of the ...
1
vote
1answer
1k views

Filesystem: How to find block of file represented by inode? [closed]

I am writing a file system for my operating system and am doing research on existing file systems before I start designing my own. I came across some slides about the System Five File System and am ...
1
vote
1answer
2k views

An existing mdadm RAID5 is not mounting, Either a problem drive or Superblock

I have 4 x 3TB NAS setup as RAID5 which has been working great for almost a year. After a recent abrupt shutdown (had to hit the power button) the RAID will no longer mount on boot up. I've run: ...
1
vote
1answer
798 views

bad magic number in superblock

I need to restore a broken partition superblock, so I get my list of backuped superblocks with : sudo mke2fs -n /dev/sdd1 And I would like to know if when choosing the one to restore, if this is ...
1
vote
2answers
623 views

I have killed my HDD

I have some trouble with my external USB 3.0 drive with 1Tb HDD. I had formatted it wrong way: I wrote /dev/sdb instead /dev/sdb1, and now I have no ability to use this drive. fdisk /dev/sdb fdisk: ...
1
vote
1answer
1k views

Recovering from bad superblock on external drive

read a few similar questions/posts and tried the solutions, still stuck. My scenario is simple, external ext4 drive was powered off (via cat) while operating, and failed to mount on boot. As I dug ...
1
vote
1answer
436 views

mdadm raid 1 how to remove raid and remove data offset to mount normally?

I have a disk that was in a mdadm raid1 with a btrfs partition. Now I want to use this partition without the raid stuff and mount it normally. I already zeroed the mdadm superblock, but now the ...
1
vote
1answer
602 views

restoring raid filesystem

I ended up with my 3-disk mdadm array not being able to assemble because each of the disks had corrupted superblocks. I tried to force reassembling the array using mdadm --create This resulted in ...
1
vote
0answers
895 views

Overwritten superblock and dd backup files recovery

Good day, yesterday I tried to extend my swap partition ('cause suspend/hibernation didn't work) and I needed to decrease size of my debian linux disk (I don't ever remember if it was ext2/et3 or what)...
0
votes
1answer
137 views

How to fix bad magic number - Superblock on Linux

I'm running a dual boot system with Windows 7 and Puppy Linux Ubuntu based " Bionic " installed on a separate partition of my main drive. Completely separate from that I have a 1Tb Western Digital ...
0
votes
1answer
2k views

File system check of the root filesystem failed, manual fsck can not fix [closed]

Linux Mint 18 on SDD with LVM ext4 Booting in recovery mode shows: ata3.00: status: { DRDY DF ERR } ata3.00: error: { ABRT } ata3.00: configured for UDMA/100 sd 2:0:0:0: [sdb] tag#0 FAILED Result: ...
0
votes
1answer
315 views

Manually backup superblock - how to & does it make sense?

Background The first block of an ext4 filesystem is called the superblock - it contains essential metadata. There are backup copies of the superblock scattered throughout the filesystem; they can be ...
0
votes
1answer
2k views

How can I view the superblock of an XFS partition?

I know that EXT superblock information can be found using dumpe2fs -h /dev/sda1, but what is the XFS equivalent of this? The best I have found so far is xfs_info /dev/sda1, but this doesn't seem to ...
0
votes
1answer
224 views

Bad magic number in super-block: dm-crypt device

I have a device that is encrypted using dm-crypt. This is a mini SD card that I use on my laptop. I've had some issues with my laptop freezing recently, and in the journal these messages come up: ...
0
votes
2answers
4k views

Can't load Ubuntu: Superblock checksum does not match superblock while trying to open /dev/sda7

I have a problem while loading into Ubuntu 17.04. This happens for the 2nd time after I booted into Windows. For the 1st time I just reinstalled the Ubuntu. I am not good at this question, so I hope ...
0
votes
1answer
474 views

e2fsck giving some error

I am playing with LVM and while doing lvreduce. I now get this error: [root@localhost raja]# e2fsck -f /dev/vg1/lvol2 e2fsck 1.41.12 (17-May-2010) e2fsck: Superblock invalid, trying backup blocks... ...
0
votes
1answer
109 views

Ubuntu won't boot [duplicate]

My laptop ran out of power and when I went to plug it in and power it on, Ubuntu no longer boots. I get directed to BusyBox built in shell that looks exactly like: BusyBox v1.27.2 (Ubuntu 1:1.27.2-...
0
votes
1answer
713 views

How to fix external HD?

I have an external HD which is divided into two partitions: an exFAT with 700GB and a LUKS partition with 300GB. I was copying from my computer to the luks partition but it got slow and stucked so I ...
0
votes
1answer
2k views

Force Filesystem Reread / Remount

Is it possible to force a complete re-read of a mounted filesystem (EXT4) from disk in a blocking manner? I have a potential situation where independent and external hardware can modify a filesystem ...
0
votes
1answer
30 views

Will relabeling a partition destroy data

Is it possible to relabel a partition that was accidentally relabeled with a different file system type? We think we accidentally relabeled sdb1 as XFS when it should have been labeled lvm(8e), after ...
-2
votes
1answer
25 views

How to clean and reboot HDDs pulled from LVM groups (showing bad super blocks)?

I have 2x 4TB HDDs that were put in an LVM group last year, ended up not really using this server due to huge issues around installing nextcloud. At some point it started giving me boot problems so I ...